The DisplayClip defines the on-monitor region, and is independent of the screen dimension. The rectangle describing the DisplayClip determines how much of the screen can be seen at a time. The screen is "shown through" the DisplayClip in much the same way a SuperBitmap is shown through a window. If the screen is larger than the DisplayClip, only part of the screen will be visible. The DisplayClip makes it is possible for Intuition to support hardware scrolling of a raster larger than can fit on the display. Intuition will take care of specifying the rectangle of the DisplayClip region based on the default screen dimensions or based on the SA_Overscan tag (if it is present), so most programs shouldn't have to specify the DisplayClip rectangle. Example 3, ScreenDisplayModes.c, illustrates opening any type of screen currently available to the system, using any type of available overscan.
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